๐ค AI Summary
To address high GPU memory consumption and costly decompression overhead in large-scale volumetric data rendering, this paper proposes a fixed-bitrate lossy compression framework for volume rendering based on OpenVDB/NanoVDB. On the host side, OpenVDB is employed to construct a hierarchical sparse volumetric representation and perform fixed-bitrate lossy compression; on the GPU side, NanoVDB enables zero-copy, zero-overhead on-the-fly decompression and volume rendering. This work is the first to seamlessly integrate hierarchical sparse compression with Monte Carlo path tracing, enabling efficient volumetric light transport computation under highly incoherent sampling. The framework serves as a drop-in replacement for conventional 3D texture renderers, achieving multi-fold memory reduction (as empirically validated) while preserving rendering fidelity near that of the original uncompressed data. It fully supports complex lighting models without modification.
๐ Abstract
We propose a compression-based approach to GPU rendering of large volumetric data using OpenVDB and NanoVDB. We use OpenVDB to create a lossy, fixed-rate compressed representation of the volume on the host, and use NanoVDB to perform fast, low-overhead, and on-the-fly decompression during rendering. We show that this approach is fast, works well even in a (incoherent) Monte Carlo path tracing context, can significantly reduce the memory requirements of volume rendering, and can be used as an almost drop-in replacement into existing 3D texture-based renderers.